[gpunto]

Goal

Add the v2 websocket connection, the second step of moving the socket to v2. It sits behind an internal flag that is off by default, so the socket still connects on v1 until a later PR flips it.

Part of AND-1637

Implementation

• ChatClient.Builder.useV2WebSocket(enabled) (@InternalStreamChatApi) makes the socket connect to /api/v2/connect and parse its frames with V2EventParser.
• The v2 socket authenticates with a frame sent once open (token, user details with custom data under custom, the chat product) instead of the URL and Authorization header. Reconnections send the user id only, as on v1. Anonymous users connect with the anonymous auth type and a placeholder token.
• The keepalive is a minimal health.check frame for the connection on v2, and the echoed connection event on v1, as before.
• A v2 frame that fails to parse is handled as on v1: dropped and logged once connected, a connection error before.

Testing

• V2SocketTest covers the v2 URL without an Authorization header, the auth frame on first connection, reconnection and for anonymous users, the keepalive frame, frame parsing, and the socket staying on v1 without the flag.
• CurrentUserFetcherTests covers fetching the own user when the v2 socket connects.

[github-actions]

PR checklist ✅

All required conditions are satisfied:

• Title length is OK (or ignored by label).
• At least one pr: label exists.
• Sections ### Goal, ### Implementation, and ### Testing are filled, or the PR is bot-authored.
• An issue is linked (Linear ticket or GitHub issue), or the PR is bot-authored.

🎉 Great job! This PR is ready for review.

[github-actions]

SDK Size Comparison 📏

SDK	Before	After	Difference	Status
stream-chat-android-client	6.25 MB	6.25 MB	0.00 MB	🟢
stream-chat-android-ui-components	11.57 MB	11.57 MB	0.00 MB	🟢
stream-chat-android-compose	13.23 MB	13.24 MB	0.00 MB	🟢
stream-chat-android-ai-compose	2.07 MB	2.07 MB	0.00 MB	🟢
stream-chat-android-ai-ondevice	1.67 MB	1.67 MB	0.00 MB	🟢

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
90.4% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud